The invention relates to a device for temporarily immobilizing tissue in the area of a pulsating blood vessel, in particular a coronary vessel, during a cardiac and/or thoracic surgical intervention.
A device of this kind is known from WO 02/28287 A1, for example.
Such devices are used in cardiac and/or thoracic surgical interventions in which procedures are carried out on the coronary vessels of a beating heart. One of these techniques is called the MIDCAB (minimally invasive direct coronary artery bypass) technique. This technique is performed through an intercostal space.
In another operating technique, the sternum is cut through along its length, and the thoracic cage is spread open sideways using rib retractors. To permit better access to the heart, one half of the thoracic cage, namely the left half, is lifted relative to the right half of the thoracic cage. Procedures can now be carried out on the beating heart without the heart having to be connected to a heart-lung machine, referred to as OPCAB (off-pump coronary artery bypass) procedures.
In procedures carried out on the beating heart, a sternal artery, for example, which has been suitably prepared in advance, is sutured directly onto a vessel of the beating heart in order in this way to create a bypass round a coronary vessel stenosis or occlusion. Since, as has already been mentioned, the heart is still beating, how-ever, that is to say making pulsating movements, it is very difficult to perform a procedure at this site.
In order to immobilize or stabilize the tissue in the area of the vessel where the bypass is to be created, the aforementioned devices, which are also called OPCAB stabilizers, have become established.
Devices of this kind comprise a pod which can be placed onto adjacent tissue on both sides of and alongside the vessel of the beating heart and which thus immobilizes this area.
Depending on its design, the pod is in the shape of a fork head with two approximately parallel prongs that can be placed on both sides of the vessel, or, as in the publication mentioned at the outset, it is made up of two individual structural parts which can each be placed onto one respective side of the vessel. The pod, or the prong, is connected to an arm, the latter in turn being connected to a stationary apparatus, for example mounted on an aforementioned rib retractor. In this way, the pod can be placed with a certain pressure onto the tissue and immobilizes the latter in the area to the left and right of the vessel on which the procedure has to be carried out.
The pod is provided with suction openings via which the tissue can additionally be sucked onto the pod by an underpressure, such that it is almost impossible for pulsating movements to take place in this area, and the operating surgeon thus has access to a substantially stationary, i.e. immobilized, operating site.
Since interventions of this kind are performed on one of the most important of the vital organs, the beating heart, whose function has greatly deteriorated as a result of pathological changes, it is desirable to be able to adapt the pod as effectively as possible to the anatomical anomalies in the contact area.
Therefore, in aforementioned document WO 02/28287 A1, and particularly in WO 00/15119 A2, numerous adjustment possibilities are provided in the area of the pod, such that the latter can be adjusted with as many degrees of freedom as possible. These include twisting, tilting and pivoting of the pod, or of the two prongs relative to one another. In this way, it is possible to permit adaptation to certain orientations of the tissue. In the final analysis, however, the tissue always has to adapt to the pod, which is made of rigid materials.
WO 00/15119 A2 mentions at one point that the entire pod can be produced from a plastically deformable material, such that it can be bent in situ into a defined orientation by the operating surgeon. However, in this case too, the tissue then has to adapt to this bent pod, for example one that has been bent in steps.
U.S. Pat. No. 6,074,375 discloses a device for introducing a liquid into the heart muscle. The liquid is introduced into the muscle of the beating heart with a kind of syringe. In order to immobilize the tissue area at the injection site, a two-legged suction pod is provided which can be placed onto the heart muscle and through which a vacuum can be established. Suction openings at the outer end of the two legs serve to suction the tissue. The legs have flexible portions in order to adapt them to the contour of the heart surface. The legs remain in the bent orientation. A soft elastic layer serves as a seal between the muscle surface and the outer end with the suction openings. Here too, the tissue adapts to the shape of the pod.
German Utility Model DE 20 2004 012 637 U1 discloses a suction stabilizer having a basic body onto which a suction rail can be mounted. The suction rail is made of a relatively hard material.
It is, therefore, object of the present invention to make available a device of the type mentioned at the outset which permits less traumatic immobilization of the tissue.